Car roof



G. G. GILFIN sept. 27, 1932.

GAR ROOF Filed April 6, 1931 wherein the roof Patented Sept. 27, 1932UNITED STATES 1 .,.T1:1\1Ti o FFICE.I

GABTH G. GILPIN, OF RIVERSIDE, ILLINOIS, ASSIGNOR '.lO P. H. MURPHYCOMPANY, OF NEW KENSINGTON, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIAcan. noor- Application-led April 6, 1931. Serial No. 527,983.,-

the type of metal the neutral axis type, sheets are adapted, arrangedrand joined together to form a roof consisting of a series of ribsalternating with channels, and the roof as a whole functionsmechanically after the manner of a beam. The principal object of thepresent invention is to strengthen and stiifen the seam construction andadapt it for better cooperation with the body portions of the sheets intaking care of beam stresses. Another objectis to secure an equaldistribution of the metal above and below the geometrical center line ofthe roof, thereby placing the neutral axis This invention relates to carroof known as vofthe roof along said line and thus enabling the maximumstrength of the metal to be obtained. Another object is to avoidextending the fastening devices from the outsideto the inside of thecar. Another object is tov utilize the space between the upper and lowerlevels of the roof sheets to accommodate'the roof seams Wholly or inpart. l The invention consists in the parts and in the arrangements andcombinations ofparts hereinafter described.T L

In the accompanyin drawin which forms part of this specifigcation anwherein ike reference letters and numerals refer to like parts whereverthey occur, p

Fig. 1 is a plan view of a portion of a car roof embodying my invention,Fig. 2 is a vertical transverse cross-section through one-half of theroof on the line 2-2 in Fig. 1,

Fig. 3 is a verticallongitudinal cross-sec.

` tion through the' roofy on the line 3-3 in vinvention form a series offlat-topped ribs A "at one level alternating with 1g. 4 1s an enlargedcross-section of one A of the vertical seams that connect the margins ofadjacent sheets, x

Figs. 5 and 6 are cross-sectlonal views Similar to Fig. 4, showing seams-of modified form. Y

Conformably to the so-called-.neutral axis type of roof, the roofsheets'l ofthe present a lserles of flat- B of substantially equal at alower level, said bottomed channels cross-sectional area point at ornear the eaves where they merge into the plane of the side portions.Along each side margin .ofthe sheet is an upstand-' v are arranged sideing flange 4. The sheets b side with their ends riveted to thesideplates 2 and with seam caps5 straddling the upstanding flan rigidlysecured t neutral axis of the roof. 1

es 4 of adjacent sheets and v ereto, preferably along the;

t Preferably the seam cap 5 is a strip of metal of heavier vgage thanthe sheets, which strlp is folded on itself and provided along` itslongitudinal edges with flanges 6 that rest on the body portions ofadjacent sheets. this arrangement, the seams are located at the middle`of the channels'B; and asthe rivets y7 extend horizontally lthrough theseam caps 5 and sheetfla'nges 4, they are wholly outside of the carwhere they are easy to drive and where they of leakage into the car.located 'in the channels B, they ject at the ridge of the car aproduceno danger need not proove the upper region of the eaves, suchseams can be kept lowenough to keep kinside the linesY estab.- lishedfor clearance of tunnels and bridges.

One of the advantages of the present car is that thq entire seamconstruction, includ ing the :sheet flanges and seam ucover, erateefciently with the middle of the in taking care of the stresses .ontheroof, especially as the metaly in the roof is so distributed that theneutral'axis of thereof as a whole is approximately midway between theupper and lower levels of the roof sheets and especially also becausethe seam construction is relatively only a 'short distance coop# Ysheets' l As the seams are level of the roof sheets; and even in the imembers of the roof structure considered asy from the verticallydisposed sides of the channels, which sides function as the web a beam.By reason of the relatively short distance between said web members andthe seam construction, the resistanceto buckling stresses is greatlyincreased and there is more cficient cooperation in taking care ofmechanical stresses.

In order to place the neutral axis midway between the upper and lowerpanels of the roof, it is preferable to make the width of the uppermiddle panel of the sheet substantially equal to the combined widths ofthe two lower side panels thereof, and to make said side portions equalto each other, especially as this locates the seam at' the middle of thechannel. The roof sheet hereinbefore described has the advantage that itmay be readily made of galvanized metal without injuring the same, andthat it is easy to apply to the car. Obviously the design of the seamcover admits of considerable variation both as to the thickness of thematerial and the cross-sectional shape thereof; and the seam-construction may be varied or strengthened by reinforcing strips ofmetal interposed between the roof sheets, For instance, in themodification illustrated in Fig. 5, the ,reinforcing strip is a flatstrip 8 interposed between the sheet anges, while in the constructionillustrated in Fig. 6,- the reinforcing strip 9 is of inverted channelshape.

What I claim is: 1. A car roof comprising roof sheets having upstandingflanges along their side margins rigidly securedl together, each sheethaving its longitudinal middle portion atxone level and its sideportions at a diferent level, the cross-sectional arca of the middlepor- -tion of a sheet being substantially equal to the cross-sectionalarea of the two side portions thereof.

2. A metal car roof having alternating.

flat-topped ribs and flat-bottomed channels formed therein extendingcrosswise of the car, said roof consisting of a plurality of roof sheetsthat have their adjacent margins connected by upstanding seams thatextend longitudinally of said channels substantially midway of the sidesthereof, the cross-sectional area of said ribs, said channels and saidseams being such that the amount of metal abovel the neutral axis of theroof is substantially equal to the amount of metal below such neutralaxis.

3.' A metal car roof having alternating flattopped ribs andfiat-bottomed channels formed therein extending crosswise of thecar,said roof consisting of a plurality of roof sheets that have theiradjacent margins connected by vertical seams that extend longitudinallyof said channels intermediate betweenthe sides thereof, thecross-sectional topped ribs and fiat-bottomed channels formed thereinthat extend crosswise of the car, said roof comprising a plurality ofroof sheets secured together along' their adjacent margins by hollowseams located between the upper and lower levels of the roof, andstiffening members secured within said hollow seams.

6. A car roof whose longitudinal cross-section comprises alternating{iat-topped ribs and flat-bottomed channels, saidroof consisting of aplurality of roof sheets that have their adjacentmargins connectedtogether by vertical seams that extend longitudinally of said channelsintermediate the sides thereof, and sti'fening members secured withinsaid seams. f

7. A car roof whose o1011 ltudinal crosssection comprises alternatmgflat-topped ribs and Hat-bottomed channels, said roof consisting of aplurality of roof sheets that have thelr adjacent margins connectedtogether byf vertical `seams that extend lon tudinally of said channelssubstantia ly midway between the sides thereof.

8. A carroof whose longitudinal crosssection comprises alternatingfiat-topped ribs and flat-bottomed channels, said roof consisting of ayplurality of roof1 sheets that have their adjacent margins connectedtogether by vertical seams that extend lon' said rib's and said.channels being substantially equal and the metal in said seam being sodistributed as to place the neutral axis of the roof as a wholeapproximately midwaybetween the upper and lower levels of the roof. y

9.: A car roof whose lon/'tudinal crosssection comprises alternatmgfiat-topped ribs and fiat-bottomed channels, said roof consisting of aplurality of roof sheets that have their adjacent margins connectedtogether by vert-ical seams that extend longitudinally of said vchannelssubstantiallymidway between the sides thereof, said seams comprisingvertical flanges along their side margins and seam caps that straddlesaid flanges, the cross-sectional area of said ribs and said channelsbeing substantially equal and the metal in said seam being so dis- 5tributed as to place the neutral axis of the roof as a wholeapproximately midway between the upper and lower levels of the roof,said seam caps being rigidly secured to adjacent seam flangesapproximately along the l neutral axis of the roof.

10. A car roof sheet having upstanding flanges along its side marginsand having its longitudinal middle portion at one level and its sideportions at a different level, the

@ cross-sectional area of the middle portion of said sheet beingsubstantially equal to the cross-sectional area of the two side portionsthereof.

Signed at Chicago, Illinois, this 2 day of April, 1931.

GARTH G. GHJPIN.

